class WildDuck extends Animal implements Swimmable, Flyable{
    @Override
    public void eat()
    {
        System.out.println("野鸭子正在吃东西");
    }
    @Override
    public void fly()
    {
        System.out.println("野鸭子正在飞");
    }
    @Override
    public void swim()
    {
        System.out.println("野鸭子正在游泳");
    }
}
